Plastic composition



render the same suitable for 5.., ASSIGNOR TO THE BARRETT COMPANY.

A COBIPOEAT'IQN OI NEW JERSEY.

ELASTIC conieosiceiio'n.

No Drawing. Application filed November 'l'o (I /Z ze/zom irfmrrj/ (once/'22 Be it known that l. linxsn'ru ll. BINKLEY, a citizen of the l nited States. residing at too Lexington Avenue. New York, inthe county oi New York and P late oi New York, have invented certain new and useful lm proveinents in Plastic Compositions. of which the 'l'ollowing is a specilication.

lhis invention relates to a material that is plastic when hot. which material is es pecially adapted tor rooting purposes. it relates more particularly to the production of a composition of mattercontaining a relatively low melting point pitch mixed with a tiller which will so. modify the pitch as to roofing purposes and which may be satisfactorily used even on steep roofs without sliding.

lillany materials have been triedhsuch as pitch or asphalt mixed with different sorts of inorganic fillers. but ditliculties have been encountered with these substances, due to the fact that some of the fillers would be injured when the pitch or asphalt was heated to be applied to the root; or the fillers would deleteriously affect the pitch or asphalt; or the fillers would not remain permanently suspended in pitch or asphalt.

At present the pitches that are used tor roofing purposes, do not stand up satisfactorily. on inclines more than two inches to the foot. The heat, particularly in the summer, from the direct rays of the sun and from other sources causes the pitch to run and slide. This running" and sliding of the pitch defeats the very purpose for which it 'as intended.

A pitch to be entirely satisfactory for steep roofing purposes should. when heated, be'easily mopped, hold heat have elasticity and adhesiveness. heal with the rays oi the sun, should it develop cracks due to exp-ansion or construction beeause of weather conditions, and be of such a eonsistency that it will not slide.or run in hot weather on any normal root inclines, and my invention meets all these requirements.

A straight pitch of low melting point will not filli the demand and neither will. straight pitch, of a high melting point, but I have found that a composition of matter eomprising pitch and magnesium carbonate will give the desired results.

By the present invention, using mag- Specificatiou of Letters Patent. P fl mqt gl $1539 29, 1920. Serial no. 42?,019,

ncsiuin carbonate. l have produced a com-- position in which this tiller will withstand, without injury, a temperature as great as that to which the pitch itself is sub ected' during its application to a roof. The filler is also very finel subdivided so that when mixed with the pitch, a composition is pro duced which has the characteristic of being smooth. 'it the same time the tiller has good suspensionqualities,-so that the danger of the same settling out of the melted pitch during a i plication is practically eliminated. The filler does not have any chemical action on pitch, nor does it produce other deleterious influences upon it. At the same time the filler mixed with the pitch produces a conniosition .which is workable at a lower temperature. namely about 350 F. to 500 F, than has been usual with the asphalt or pitches heretofore used for steep roofing" purposes. The composition thus produced seems to be self-healing. That is, if when cold it becomes accidentally cracked, the cracks subsequently mend on warming so as to produce again a continuous sheet. lVhen spread out it is smooth and will maintain a high gloss and sheen, and at the same time. will not slide or run to an appreciable extent. even when exposed to the directrays of the sun in the hottest climates. Th s composition also has the advantage over present roofing pitches or compositions in that it holds heat for a much longer period and is, therefore, easier of application.

ln practicing this invention 1- mi); pitch with a. certain percentage of magnesium-car bonate, thereby producing a composition oi matter which has a higher melting point than the pitch but at the same time composition can be rendered plastic by the application of sufficient heat. so that the same is capable of beingapplied to a root by means of a mop.

As a specific illustration of my invention 1 will give the following proportions, but it is to he understood that this is merely illustratiye of the invention as the proportions and melting point of the pitch may {be Varied over a Wide range without depar ing from the spirit or scope of this in? vention. Y i

I take coal tar pitch of a. melting pointef water method) and containing about 25% of free carbon.

This is mixed with about one-ninth as much by weight of magnesium comes .well distributed throughout the mass.

carbonate. The mixture is heated and stirreglso that the magnesium carbonate be- The melting point of the finished product is thereby increased to about 208 F.

.larticles of pitch .of the proper melting point can be mixed with magnesium carbonate and the mixture dumped into an agitating still and heated to the proper temperature; or coal tar can be distilled until 7 the residium is "a pitchgof the proper melt-' ing point, whereupon the magnesium carbonate may be introduced into the molten pitch; or coal tar and the proper amount of magnesium carbonate can be mixed-together and placed in a still where the proper amount of volatile constituents are dis tilled off, leaving a residue of the proper melting point. It is clear that, irrespective of the method: employed, it is desirable to ob 1. A composition of matter comprising pitch and magnesium carbonate, said composition having a melting point of about 2. A composition of matter comprising pitch of a melting point of about 160 F. and magnesiui'n carbonate.

8. A composition of matter comprising pitch and magnesium carbonate in substantially the proportions of 9 to l by weight.

In testimony whereof I atiix my signature.

KENNETH L. BINKLEY. 

